Variation Facts and Fallacies

Lens sharpness is widely discussed on the internet, so it shouldn’t come as any surprise that lens softness is also a major topic. However, my experience both as a photographer and as the owner of a lens rental business has shown me that much of this discussion is based on a fallacy. So just what is it reasonable to expect from a lens and how doggedly should you pursue the ‘best copy?’

Fallacy:

Noun - "an error in reasoning resulting in a misconception or presumption"

A bit of background

When I started in photography most of the forums I learned from had at least one thread a day about someone’s 'soft lens.' They knew the lens was soft because their camera worked 'fine' with all their other lenses. After a few years of running a rental business, though, I found myself in the following situation three or four times a week:

'The lens you sent me front-focuses, it's not good.''OK, we’ll overnight you a replacement.'

Only to find, when the first lens came back, that all our tests suggested it was perfectly fine. And the customer is very happy with the replacement lens - apparently, this one is 'fine.'

So what causes this problem? It's rather simple, actually. The fallacy here is the definition of 'fine.' Most people assume that 'fine' means, 'perfectly calibrated.' It became apparent to me that cameras and lenses are not perfectly calibrated, but rather, they all have some variation. That realisation shouldn’t have been shocking; every manufactured product has variation, why should cameras and lenses be any different?

For the next several years I continued to investigate this issue, writing articles about it as I went. Reading all of them now is an overly-long exercise and I’ve learned a lot since I began writing on this subject. So it seems time to put a summary article together.

Manufacturing variation affects all lenses from all brands – the only difference is the tolerance levels considered acceptable.

Some Semantics

In most online discussions, things derail when different people understand the same terminology differently. Discussions of lens quality are particularly prone to that, so let me define the terms as I intend to use them.

A soft or bad copy is a copy of lens X that clearly does not perform as well as other copies of lens X. There are bad lenses out there. They happen.

A design choice affects all the copies of Lens X. Every lens has some design choices made that we may not like.

Copy/sample variation is a slight difference that can be detected between different copies of lens X, or different copies of Camera B. Copy variation is detectable, but usually not significant (compared to a bad copy which is always significant).

The Search for the Holy Lens Grail

Before we go further, there are some people that should probably stop reading here. If you ever think 'for $1,500 I demand perfection,' this is not the article for you, it will just get you upset. The laws of physics are not suspended, nor are techniques of manufacturing altered, just because you demand it be so. If you enjoy The Quest for the Perfect Lens and other fantasy games, just move along and save yourself the aggravation of being administered this particular dose of reality.

Why Variation is Inevitable

First, I should mention that the problem has received more attention in recent years, oddly enough, because our equipment has improved so much. A 6MP crop-sensor camera didn’t expose the flaws in a lens that now, a 24MP full-frame camera makes painfully obvious. Better lenses contribute too: when a lens had four really soft corners it was hard to tell if one side was worse than the other. On a newer lens with sharp corners the difference may be instantly obvious.

It’s probably not a coincidence that photographer and blogger Lloyd Chambers brought attention to the fact that camera mounts aren’t always perfectly parallel to the sensor when he was testing Zeiss ZF 21mm lenses on a 24MP Nikon D3x. There's every chance it would not have been apparent if he had been shooting a lesser lens on a lesser camera.

The key thing to realize is that the problem is not limited to one brand, one type of lens, or even just SLR gear. Landscape photographer Joseph Holmes found significant variation in medium format lenses and focusing. Testing website SLR Gear found a batch of 50mm lenses that were all softer on the right side than the left. At Lensrentals we found a group of 300mm f/4 lenses from the same serial number run almost all suffered electrical failures. Why is this so?

Manufacturing Tolerances

Manufacturing tolerances are just that: a range of acceptable values, not an exact point. In other words, what is specified as a 1/4 inch diameter screw may be anything between 0.247 inches and 0.253 inches in diameter (see this chart from an internationally-renowned industrial fastener manufacturer). The machines that make them can’t be more accurate than that at reasonable cost.

Did you know that every time a glass manufacturer makes a run of a given optical glass, the refraction index and dispersion vary a tiny bit? The glass manufacturer furnishes a melt sheet to the lens manufacturer so they can make tiny adjustments in thickness or curvature of that element to compensate for the differences.

The glass is probably a tiny source of variation compared to the other components that make up a lens or camera. In addition to the multiple glass elements, there are clips, shims, and grips that hold them in place within the lens. There are helicoids, barrels, gears, and rings move them around to focus. Electrical motors and circuit boards tell them what to do, and, as Chambers has shown us, even the lens mount that connects the lens to the camera is a source of variation.

Cross-section of a Zeiss 21mm lens. Note all of the clips, shims, and barrels holding the elements in position.

Many, if not most, of those components are outsourced to other companies or factories. A change in subcontractor could result in a slightly different part being supplied. Something as simple as a set of ribbon cables more likely to crack or a solder that is slightly less conductive being used on a circuit board could result in significant changes to a camera or lens.

If you delve into the manufacturer’s parts lists (when you can get them) you’ll find they take these variations into account and plan for them within a given tolerance range. For example, if you need to replace the front element of your Nikon 14-24mm lens (part # 1K104-xxx) you need to replace the adjustment washer behind it with one of five specific thicknesses - each copy of the lens requires a slightly different thickness for proper spacing of the front element to focus sharply.

There are numerous other variable-sized spacers and parts for every lens (most lenses have variable thickness spacers in at least three different places). In many lenses even the lens mount comes in several thicknesses or with shims so that the image focuses properly on the sensor. As someone who has to shim lenses fairly frequently, I can assure you it can be done close to perfection, but not perfectly. When a 0.06mm shim is indicated, we often have the choice of 0.05mm or 0.07mm shims - close, but not perfect.

Similarly, the lens must be electronically calibrated. The circuit boards inside each lens with its own AF motor contain adjustment screws to calibrate the frequency and current of the electronic pulses sent to the motor used to move the lens during focusing. Manufacturers don’t build in this adjustment because every lens is exactly the same; they build it in because every lens is slightly different and adjustments are necessary. And by the way: the factory manual gives an acceptable range for the adjustment, something like 150 +/- 2 KHz.

It’s not my purpose to list every source of variation in a given copy of a lens or camera body. They are far too numerous. But just to give an idea of some major ones:

A lens has eight to 23 elements, each of which may vary slightly in its spacing from the other elements, centering along the axis of the lens, and tilting from right angles to the axis of the lens.

The focusing and zooming elements must move certain distances front to back within the lens and during their travel their tilt or centering may vary slightly.

The barrels and helicoids, and various slots in them, must machined so that the elements are not only aligned properly within them, but they are aligned properly with other barrels.

The lens mount may not be perfectly parallel to the camera’s sensor.

For everything on the list there is a slight variation within an allowable tolerance. You can demonstrate this for yourself if you have some friends (or camera club members) and can get several copies of the same lens. Mount a camera to a tripod and focus on a target that is very visible in live view at 10X magnification. Then, just change from one lens to another and watch the target be a bit off center in different directions with each lens. Just a bit for most lenses, but you might find one that's off target by half of the screen or so.

Camera bodies are no different than lenses with regard to variation, and in fact could be even more problematic. Is the sensor perfectly parallel to the lens mount? Is the AF sensor properly calibrated to the imaging sensor? Is the AF mirror exactly aligned and angled in relation to the AF sensor? The list goes on and on. And in every case the camera is made nearly perfect, but not exactly perfect.

Lens-Camera Matching

During, and at the end of, the assembly process, the lenses and cameras are tested to make sure they are within the manufacturer’s specifications. If they are out-of-spec and get by quality control, then someone, somewhere gets a truly bad camera or lens. It doesn’t happen frequently, but it happens. When it does, it isn't a subtle call; it's very obvious the lens is bad. In mass-produced elements, quality control is likely to be conducted on a 'sample' basis - only one in every ten or every hundred units will be checked.

But even the cameras and lenses that meet specifications are still going to vary slightly. Many people think, 'I’ll try eight lenses and take the best one.' The reality though is that the only sensible definition of 'best' is 'best with the camera body you are using,'. This is because there is plenty of room for variance in the behavior of bodies, too.

Let’s consider just the lens mount as a theoretical example. First, we say the lens mount of a camera must be parallel to the sensor with a range of +/ - 0.05 degrees (I have no idea what an acceptable range is, I only know that they cannot consistently be made perfectly parallel). Then, let’s say camera A's lens mount has a tilt of 0.04 degrees to the right. Lens #32 has a tilt of 0.04 degrees to the left. The two tilts would cancel each other out, all would be magical, and the owner would write sonnets on the various forums praising his lens.

But let's say he sells his lens to someone whose camera's lens mount has a tilt of 0.03 degrees to the left. The lens and camera now both tilt to the left and the new owner may say, 'the lens you sold me is a bad copy, it’s horribly soft on the sides.'

And this is just tilt. The mounts may also vary in thickness. There is variation, too, in autofocus systems. Certainly more than there is in lens mounts. Through-the-viewfinder manual focus will also vary (you might be surprised to know that viewfinder focusing screens are shimmed by hand). Even exposure metering varies slightly from camera to camera, and requires recalibration if it’s out of specification.

The bottom line is every lens varies slightly, in several respects. And every camera varies slightly too, in a number of different ways. A given lens on four different cameras will behave slightly differently on each of them, and four different copies of the same lens will each perform slightly differently on a given camera body. How differently? Well the short version is you probably will notice the differences if you’re a 'pixel-peeper'. If you use cameras and lenses to take pictures, though, it would be very unlikely you’d notice normal variation, even with large prints. The one exception might be high quality wide aperture lenses because the narrow depth of field may make subtle differences apparent.

Comments

I tested 3 different copies of Nikon 16-35mm f/4G VR on my D700, only one of them does not display severe de-centering : with the two other copies one (or more) of the corners are significantly softer than the other corners at f/4. it was shocking to say the least.

If wide angle shots are your bread and butter, the moral of the lesson is buy at least 3 copies of the wide lens you want and cherry pick one. it definitely was worth it.

Had the same with my copy of the 16-35 which I bought to complement my (very sharp) 14-24 which is prone to raindrops :) It showed decentering. Took it back to the shop, got another copy, no problem. Had the same with a 10-24 DX by the way, even worse de-centering. The second copy was fine too. Quality control nowadays... :(

How come and so many readers here ignore elementary principles of manufacturing? The same stands everywhere...Your 200 ps car may deliver from 192 to 208 ps and believe me the manufacturers will never tell u that...It is also rather rare your car to deliver 201 ps.... Usually delivers less!

One reason I like primes. Zooms are obviously more complex with the extra movements and elements that are necessary to make them work. This, coupled with plastic parts that seem to require wider tolerances, make for a better chance to get a dog. And that I have.

I love the silky smooth focus rings of the old metal lenses and the no wiggle when you shake it rigid body. I must say that after collecting numerous types of these lenses, sometimes two or three copies of the same lens, I never had one that was soft on one side or had some other quality issue.

I once had a 35 f/2 prime lens that was plain awful. Sent it to the service center and they acknowledged the lens was totally out of whack. Nothing to do with AF calibration. It was a totally different lens after servicing.

When the camera manufacturers started including a back/front focus adjustment feature in their camera's that was an admission there were indeed focus problems between many lenses and cameras..That fact is not a FALLACY!!!

This added feature has saved the camera makers from repairing literally thousands of returned lenses...They initially didn't listen or care about customer complaints about focus issues until they were swamped with returned lenses, based on what customers had learned from reliable sources...Had it not saved the camera makers money they still wouldn't care...

It was an admission that with digital cameras, many users can and do pixel peep looking for any issue no matter how minor. In fact, I believe that modern lenses for digital cameras got sharper because the buyers are more critical. The technology of "fixing" the lens in-camera or non optionally in raw has reversed that trend for some camera systems (Micro Four Thirds for example).

Micro focus adjustments are a real benefit, not a sign of the apocalypse. I suspect that the feature is rarely used, and improper use probably causes manufacturers to spend more time and money dealing with pixel peepers who aren't quite clear about how to do micro adjustments.

Yes, it's all about money. If you demand a high level of precision, you should be prepared to pay much more than consumer product prices for your camera gear and its maintenance.

... somewhere gets a truly bad camera or lens. It doesn’t happen frequently, but it happens. When it does, it isn't a subtle call; it's very obvious the lens is bad."

Not necessarily. One can have a lens that is significantly more out of spec than a "normal" lens, but not to the point that it is "very obvious." In fact, it is much more likely that a lens would be out of spec by a significant margin, but not "very obviously," than that it would be out of spec "very obviously," for several reasons:

1) Lenses that are "very obviously" out of spec are much more likely to be spotted and removed from distribution before they are, well, distributed.

2) Lenses that are only out of spec by a significant margin are more likely to occur than lenses that are "very obviously" out of spec, from a statistical perspective.

Very interesting article. Like someone said below, microadjust should be standard in all DSLR:s, a lot of the complaints could be eliminated. It's one thing to turn my old analog Leica M3 in for calibration with a specific lens, but with a DSLR we should be past that, especially since the technology is included in a lot of the more expensive cameras.

That said, I have never encountered a "lemon" or sent a lens back or to be calibrated.

It's not useless for zooms it's just imperfect. And adding a second adjustment for the wide and the tele end of the zoom range just begs for another for the middle. Varifocus action isn't the same for every zoom design.

Very thorough analysis. Of course, it doesn't take away the wonderful feeling you get when all the stars are lined up in your favor and you find a great combination of camera body and lens that works great for you.And yes, I realize that being a fussy customer is not going to make it happen any more often.

Thank you very much for this excellent article. It will save me a great deal of (unnecessary) stress in the future. In the past, I have agonised occasionally over "soft" lenses (and spent more money than necessary in fruitless attempts to cure them) but now understand the pointlessness of seeking perfection.

I enjoy all of your articles and often bookmark and forward the links to those that find "flaws" in their gear...........they seem to quickly clear up any misconceptions they have about "soft" lenses ..........thanks for your time & effort.......

Thanks for a good article! For me this has helped clarify and reinforce what I already suspected, but did not have the time nor the equipment nor the skill to determine for myself. I guess I'm lucky that for me, so far, all my lenses have fallen into the "acceptable" category for sharpness and performance.

Thank you so much for the kind words -- but I can't take all of the credit. Richard Butler was instrumental both in the idea of a summary article and in editing it. He put in so much work that I asked him to list himself as co-author. He wouldn't do so, but he should have.

Well, then... a most heartfelt, and sincere Thank You to both of you for putting this all into perspective. Most of us who have used cameras for decades really "knew" all this, but have probably chosen to ignore it... much to our regret.

Personally, I found it most beneficial to have it pointed out that, really, the auto-focus is probably the single biggest contributor to unhappy results, all other things being equal.

As well, and as is kind of stated, a bad lens is a bad lens and is more than likely very obvious... the other variables on the other lenses may disappear into the background noise. :)

Well.. I've owned a fair few lenses and never sent one back - I have Canon and Leica glass and I've never experienced an issue with any of them. Perhaps I'm lucky - but if i was to go by people whining on forums about 'soft copies' then I'd be forever adjusting and not shooting.

No client of mine - or publisher of my photos has complained they are 'soft copies'

An excellent article. As I learned in Six Sigma training, managing statistical variance is the essence any manufacturing process. Different lens (and camera) manufacturers will have different standards for these variances ... what is acceptable and what is not. The ones with the tightest tolerances will have fewer bad lenses on the street and (we can assume) less variance among copies. Tighter tolerances cost money; lenses with tighter tolerances will cost more than lenses with wider tolerances. Hence, it is no accident that lenses from certain manufacturers have better reputations than others and that many lens manufacturers have different lens series based on quality and cost. You get what you pay for!

Thank you! It is good to have a voice of reason to stop the madness. I have always wondered how the same people always get boatloads of "unusably soft" lenses. I have only bought one lens that was DOA right out of the box in all my years of photography. My other lenses just work work work.

As someone who's been involved in manufacturing for 35+ years, I understand variation in both the manufacturing and assembly processes all too well. It's really no small achievement that mass-produced items are nearly identical, within microns, on a consistent basis. Modern machining and measurement methods, both computer controlled, are largely responsible, but credit must also be given to the engineers who design things that are "manufacturable", at least most of the time. :)

I've had one bad lens out of the dozens I've bought. It was well regarded and tested OK out of the box, but then it stopped being able to acquire critical focus in the middle of a shooting session. Apparently something within the lens shifted after it passed its initial shakedown. Sent it back and that was that (always know your dealer's return policy before the purchase).

Bad lenses are rare, but the people who examine them with anal zeal are not and this article won't cure them, sad to say.

Even the gauges used to measure parts have tolerances so even the measuring devices aren’t perfect. Physical Perfection along with beauty can never be truly attained only an approach toward it can be made.

Thanks for an excellent article, well written. It certainly held my attention from start to finish, which is an achievement in itself.As for the subject, I'm constantly surprised at how people haven't realised the concept of manufacturing tolerances. Maybe I take it for granted, having started my working life in manufacturing. I'd just like to add, the same concepts apply to everything ever manufactured (the brakes on your car!), so for anyone worrying about tolerances, I'd suggest the ones used in lens manufacture move towards the bottom end of the concerns list.

Yes, but there's another factor to consider: cost. The additional cost of controlling tolerances such that two components never combine to exceed overall acceptable system tolerances is very high. The additional cost of each "9" (e.g., 99.99% vs. 99.9%) in performance is not linear.

Controlling a component to a tolerance of, for example, .025" may easily be 10 times the cost of controlling it to .05". For the relatively few cases that combine in a bad way, it's probably not cost effective to try to prevent it. Would you pay 10% more for your bodies and lenses to guarantee that never happens? In a competitive industry, when you know your competitors won't do that, you can't afford to do it either.

Once again you confuse the compositional and technical qualities of an image.

Once again it needs to be pointed out that both elements are important. If we can only have one (a false choice), then of course the compositional should take precedence. But if that image lacks sharpness, then it distracts from the well-composed subject matter.

I think you'll find avoiding simplistic black or white statements will give you a more accurate view of most topics.

On top of this is that people on forums who have a bad copy of anything will make the most noise and really make thing seem far worse than reality.For instance if 90% of people were happy with their lenses then they just use them. Another 9.99% get on a forum and show images. Then 0.01 percent of people in the world get a bad copy, look on the forum to see if someone else has a bad copy too and then others start pixel peeping and pretty soon everyone gets paranoid about getting a bad copy or the lens now has this baggage "did u get a good copy?"So also then there is a totally false truth because if most of those people who have a bad copy go to the forum and post and are vocal about how bad things are and the rest who have a good copy dont care, then this vocal minority suddenly becomes overwhelming. In reality 100x1000 of lenses have been sold and there are many happy people with just a few duds.Not too mention the forum trolls that seek to enhance a bad rep for their own gain.

2) Owners of an acceptable lens-body combination just have to stand the inevitable random scatter ...

My 2Cnt: He is so right! If you experience about 25% randomly unacceptable focused shots, you will greatly improve your yield by taking a second independently focused shot. The probability of both shots being bad diminishes: 0.25X0.25 :). And by the way, just stop pixel peeping, life is too short

Well TomB and JonF, half of the four Canon "L" lenses I've owned in past years were clearly defective from the get-go (17-40 and 24-105), with a distinctly soft side seen (but only if you looked!) in prints larger than 8.5x11, and above 4x mag. on the LCD - pixel-peeping, if you wish. My Nikon F lenses of the 60's were much more uniform in their quality as seen in my 16x20 B&W's.

Not to care at all about taking the minimal time it takes to look for lens softness is kinda like the lazy woodcarver who never sharpens his tools, and tolerates the rough outcome as "the nature of the wood", or other such drivel.

Pro or not, you folks admittedly don't look very closely and must not print very large, deal with picky photo editors (that would be all of them), or have been jackpot lucky with all your lenses - a most unlikely situation...

My wife is fat, a lousy cook, and keeps a messy house. So I find your article nice and even inspirational. Now I hafta call for a replacement or get my money back -- or chalk it up to the imperfect world where the ideal can only be found through the eye of a perfect lens.Cheers,

Very good story. You are telling things, I somewhere had in my mind, but could not prove. I could not even find the right words to tell. Your equipment did help you to by that. And you have written some great articles. Thanks for this in depth article. It is of great help for me. Will be in my mind every time I buy a lens.

Lower standards, absolutely not. Read Lightroom above and you'll understand my point. To state it alternatively; human inventions have limits and tolerances, thus, if you expect perfection you'll be disapointed. Everything you purchase carries with it a warrantee of merchantability. This means it should do the thing it was designed to do, and if it doesn't get a refund or exchange. But don't expect perfection.

So, in conclusion, don't blame Lensrental.com (or Amazon/DPR for that matter) for a lens that does not perform well on your camera.

This article states nothing new that a few years of buying lenses should have told you already but leads the newbie to a conclusion found down the path of abject obedience and maybe unintentionally provides fodder for fanbois whose manhoods are threaten by reports that their favorite lens ain't all dat.

Let's say you rent a lens from Lensrental.com (or buy a lens from Amazon/DPR) and it front focuses on your camera but not on the test cameras at Lensrental? What are you to do?

Writing an article that positions one as an expert in a field is a common and acceptable business practice. However, a conflict of interest is almost always present. Good can still come of it if one is wary of the pitfalls.

boho I'm actually amazed at how you can infer "lower my standards in order not to harm your business..." from the article as it mentions nothing of the sort.

The article merely lends an understanding to a reality about lenses and cameras in the context of reasonable tolerances. If you expect (and recognize) what's reasonable (a lens that's in tolerance but not necessarily optimized for your particular camera), then you'll be better equipped mentally to detect the truly unexpected (an obviously bad lens). The article isn't saying do nothing after paying $2k for a "bad" lens. The article merely details why lenses are often perceived as "bad".

Regardless what business the writer's in (selling/renting lenses) the facts about lenses and cameras have not changed.

How novel: things, like mankind itself are imperfect. The Hubble space telescope mirror needed replacement even though it cost millions of dollars and was the most precisely engineered optic element in history.

Imperfect creation notwithstanding, we posses free will to endeavor to greater heights. Witness the accomplishments of Bach, Einstein, Michael Jordan and Salk-Sabin. But with that come measuring tools and improved insight to reveal flaws. Concomitant is the demand for perfection. The author, taking the human condition into account, warned us of this.

We demand greater, more innovative and clever assemblies to reach the euphoria we experienced once upon a time. I too would like a car that gets the equivalent of 100mpg, 0-60 in 3 seconds, seats 5 adults comfortably, has every electronic device imaginable, can manuever better than an F22, and almost never needs service.

There remains a lot we can learn from our forefathers, chief among them our own humanity.

There are really lensese out there that DO overcome some of the old physics issues and the design and production choices that some companies make are really annoying.

Take the 17-55 2.8 by Nikon and compare it to the 24-70 2.8 - One is DX and the other FX, but for their counterpart cameras they are basically designed for the same kind of photography and the 24-70 is a much better lens!!! It can produce very sharp images from edge to edge even at 24mm, where as the 17-55 cannot.

I think it's reasonable for Nikon users, especially professionsals to criticize Nikon for this and if I ever start shooting for money again, I hope Nikon will address (what I see as) the huge design flaws in the 17-55!

In 44 years of fairly serious photography I have gotten 1 "bad" lens out of 12 I currently own. It was pretty obvious, I sent it back. The next one was also bad. The store would only replace that one if I signed a waiver that that was the last replacement. I foolishly did and got a third bad copy - I since have given that one away (to someone who is happy with it). All the other 12 have been more than good enough for me printing at up to 17X22. And I only judge the quality in a print. Malcolm

I have to admit that I am probably such person. I rarely print. I just have little use for printed images. However, I do pay a lot of attention to get the best compositions. Yet I greatly enjoy looking at all the details viewing the images 100% on the screen. A sharp image at the pixel level gives the a greater sense of reliving the scene and allows for further cropping, if desired. Why would I accept a quite soft 100% view that would "would not matter" when printed? Cropping seems very useful in wildlife, bird, macro, and street photography.

I'm always surprised how certain professional photographers tell others to buy the most expensive lenses, always use tripod, mirror lockup, etc, but then despise that people subsequently are enjoying their sharp pictures also at 100% on the screen. If this is how most people enjoy their photos, which is very demanding on equipment, this drives the market for better (lower tolerance) new lenses and cameras, right?

The variations in AF is something I have noticed myself. Yes every camera focuses a little different each time you let it focus on the same subject. But I can tell from experience that there is a noticeable difference in the amount of variation in cameras. Entry level cameras have a 'large' tolerance, prosumer cameras a smaller tolerance and pro level cameras have a very small amount of variation.

tighter tolerances are more expensive in terms of production which explains the higher prices for professional level cameras and lenses.

That article sums it up pretty well. What I miss is a clear statement that AF adjustment is a must-have feature in today's cameras, no matter in what price category. Unless some pressure builds up from customers, manufacturers will continue to withhold that feature from lesser bodies. That's why I think awareness about that topic must be raised.

Thank you for sharing your vast experiences with us Roger. I for one can rest easier seeing the sharpness variables put succinctly together and having to accept that there's noting perfect in this life.As kids we shot Brownies and Instamatics and were happy with the results - a memory to be shared and cherished. Now we have moved on to sharpness, artistic content et al which in the end are probably forgotten after the initial 'wow that's nice' for those of us non-professionals anyway.

So let's see. We are paying a lot of money for a quality lens. But then for X Y Z excuses we are going to get an inferior lens? EXCUSE ME! What a load of bull! So typical of nowadays! If you are charging a wonderful price for a wonderful lens, I expect your lens to be wonderful.

But no, we should pay for full quality, when manufacturers to save costs move over to cheaper countries with cheaper workforce and lower quality checks, leaving a lot of people unemployed.

But we should understand? Well no, sorry. F U . Not only we don't understand, we don't want to. And we will not.

If a product is sold saying it ill meet certain standards it should. The rest is a load of lame excuses, and if you ask me, a fraud.

Think you missed the point of the article. there are engineering tolerances that have to be taken into account. For want of a better word it's called 'physics'.Guess you never take a bad photograph, it's always your equipment right?

Yes there are tolerances, but tighter tolerances cost more - more to manufacture, more to inspect, etc. Each company makes decisions on what tolerances are good enough - it's statistical-based analysis. Sometimes the tolerances of lens and camera add up in a bad way. If they do there is nothing keeping the purchaser from sending it in under warranty or sending it in for adjustment on their own dime. Unfortunate, but true.

LightRoom says he pays good $$ for his equipment, but how much more would he be willing to pay to get a 100% perfect lens and body? 2x, 3x, 4x more?

I've had no problems with sending lenses in to Nikon with proven problems and getting them to fix it (however if you just say it's not functioning well w/o any photographic proof they typically won't do much).

It's the same way with cars or any other item composed of many high precisions parts - sometimes you get a bad one.

Then of course their are variations in tolerance due to thermal coefficients of expansion differences between components which will cause variations in the dimensions of parts at different temperatures.So we need a lens mated to a camera body at constant temperature - who's in line to buy a bridge camera with close tolerance temperature control weighing 2 tons at $100,000?

@ Lightroom, You're not getting an inferior lens, you're getting a lens/camera combination built within what the manufacturer deems acceptable limits. These limits have to exist as perfection doesn't exist anywhere. They even managed to get the Hubble telescope out of spec the first time, which I'm sure cost a bit more than your camera lenses. When they fixed it, they only returned it to within "acceptable limits".You say you want "full quality", what's your definition of full quality? perfection?"If a product is sold saying it ill meet certain standards it should" - nobody's saying they don't meet certain standards, in fact, that's the exact opposite of what Roger is saying, most lenses do meet these standards. Some my not, but that's life (or statistics). Nothing & nobody is perfect.BTW, I've done 100% quality control checks in manufacturing myself & can confirm that out of spec parts still get through.

The more complicated to make the lens is, for example 14-24 2.8, or 70-200 2.8 (big $$$ lenses) there is a bigger chance that some of those 500 mechanical and optical parts inside is not perfect.That`s why I shoot 50 1.8, the most simple lens to make, the cheapest lens to make, and probably the most performing lens there is.

Latest in-depth reviews

The Fujifilm X-H1 is a top-of-the-range 24MP mirrorless camera with in-body stabilization and the company's most advanced array of video capabilities. We've been shooting with one for a while now and have put together a gallery, a sample video and some preliminary analysis.

Panasonic's Lumix DC-GX9 is a rangefinder-style mirrorless camera that offers quite a few upgrades over its predecessor, with a lower price tag to boot. We've spent the weekend with the GX9 and have plenty of thoughts to share, along with an initial set of sample photos.

Panasonic's new premium compact boasts a 24-360mm equiv. F3.3-6.4 zoom lens, making it the longest reaching 1"-type pocket camera on the market. We spent a little time with it; read our first impressions.

The Panasonic GH5S is best understood as an even more video-centric variant of the GH5. We've tested it in a range of circumstances to see whether the video improvements are worth the loss of stabilization.

Latest buying guides

Landscape photography isn't as simple as just showing up in front of a beautiful view and taking a couple of pictures. Landscape shooters have a unique set of needs and requirements for their gear, and we've selected some of our favorites in this buying guide.

Quick. Unpredictable. Unwilling to sit still. Kids really are the ultimate test for a camera's autofocus system. We've compiled a short list of what we think are the best options for parents trying to keep up with young kids, and narrowed it down to one best all-rounder.

If you're a serious enthusiast or working pro, the very best digital cameras on the market will cost you at least $2000. That's a lot of money, but generally speaking these cameras offer the highest resolution, the best build quality and the most advanced video specs out there, as well as fast burst rates and top-notch autofocus.

Are you a speed freak? Hungry to photograph anything that goes zoom? Or perhaps you just want to get Sports Illustrated level shots of your child's soccer game. Keep reading to find out which cameras we think are best for sports and action shooting.

Ricoh has announced an updated version of its K-1 full-frame DSLR. The Pentax K-1 Mark II gains an additional 'accelerator' processor that enables improved image processing as well as a handheld version of its Pixel Shift Resolution mode.

For a limited time this summer, current K-1 owners will be able to send their cameras in for a circuit board replacement, essentially upgrading to a Mark II. They'll even get a Mark II logo swapped in on the front of the camera.

Panasonic has continued to develop its organic/CMOS image sensor tech, and the latest breakthrough is big: an image sensor that can shoot 8K at 60p, boasts incredible dynamic range, and has global shutter capability.

Services like Copypants and Pixsy help anybody find copyright infringers, send take-down requests, and quickly demand licensing fees and damages. But do these automated systems also open the door to prolific copyright trolls?

The new 5x4-inch field camera was designed by UK photographer and custom camera maker Steve Lloyd, and it promises to be lightweight, easy-to-use, unique, affordable and upgradable... as well as a bit funky.

Camera accessory manufacturer Really Right Stuff is relocating. The company is moving its headquarters from California to Utah, citing rising costs and promising 'expansion on every level' as a result of this move.

Fujifilm's new X-H1 sits above the X-T2 in the company's X-series APS-C lineup. At the X-H1's launch in LA last week, we sat down with the camera's product manager, Jun Watanabe, for a detailed look at the new camera.

The so-called 'Prosthetic Photographer' uses AI to continuously scan the environment for 'ideal' scenes. When it sees one, it uses electrodes to zap the photographer, forcing them to press the button and take the shot. It's an... interesting idea.

A helicopter pilot and his student claim a civilian drone was the cause of their crash landing last week. If their story is confirmed by an ongoing investigators, this incident would mark the first time that a drone has caused an aircraft crash in the US.

Lensrentals' Roger Cicala just tore down the Sony a7R III to see just how much Sony did (and didn't) improve the camera's weather sealing over its predecessor. The results are a "good news, bad news" deal.

Samsung just set a new solid state storage milestone with its new 30TB SSD, the Serial Attached SCSI PM1643. This monster was built for enterprise use, but we can't wait to see this tech trickle down to consumers.

On this week's episode of The New Screen Savers from the TWiT Network, DPReview Science Editor Rishi Sanyal talks with host Leo Laporte and co-host Megan Morrone about some of the newest tech trends in smartphone cameras.

A blockchain crypto-art rose based on a digital photograph by Kevin Abosch was just sold for the equivalent of $1,000,000 USD in cryptocurrency to 10 equal investors. If that last sentence made absolutely no sense to you, read on.

Swiss Olympic skier Lara Gut wiped out on a run last week, and slid straight into a group of photographers shooting the action from the sidelines. Getty photographer Sean Haffey kept on shooting as Gut slid towards (and eventually hit) him.

There was a time when Fujifilm mirrorless camera users may have felt the need to go to another system to shoot video. Thanks to a new camera and a couple of lenses, they suddenly have some sweet options.

The Rotolight Neo 2 is an LED light panel with the capability to fire its LEDs fast enough and bright enough to act as a strobe. Is it enough to make stills photographers re-think their old-fashioned speed lights? Read on and find out.

Sony has made something of a break-through in sensor development with a new backside-illuminated CMOS sensor that is capable of global shutter, a huge improvement over current CMOS global shutter technology.

Microsoft has released a new "Ultimate Performance" mode for Windows 10 Pro for Workstations—a mode that throws all power management out the window (so to speak) in favor of the best possible performance it can pull from your hardware.